The Trump administration issued a memo late last week revoking two federal directives implemented under President Obama that had blocked a controversial water project in California’s Mojave Desert.

An acting assistant director at the U.S. Bureau of Land Management (BLM) rescinded two legal guidances that reinforced the agency’s 2015 decision that Cadiz Inc. could not use an existing federal railroad right-of-way in its long-standing project to pump groundwater from the project’s planned well field in the Mojave Desert and sell it to urban areas throughout Southern California that rely on the Colorado River Aqueduct.

While the BLM’s one-page order didn’t specifically mention the Cadiz project, it eases the way for the company to argue for the reversal of the findings of the agency’s California field office, which said the company needed federal approval to construct its 43-mile water pipeline. The memo also noted that any future right-of-way decisions will be determined by the BLM’s office in Washington, D.C.

Cadiz CEO Scott Slater told the Los Angeles Times that he was “cautiously optimistic” that the BLM’s reversal will allow the pipeline to be greenlit. Under the Obama administration’s order, Cadiz would have had to go through a lengthy and pricey federal environmental review process if it wanted to construct its pipeline on government-owned land.

The resource company hopes to pump groundwater stored in its privately-owned Mojave holdings to supply 100,000 households. If successful, Cadiz stands to make between $1 billion and $2 billion in revenue over the project’s 50-year lifespan.

The pipeline has the support of many local lawmakers, including the San Bernardino County Board of Commissioners, which approved the project back in 2012. The board argued that the project would be a boon to the local economy by creating thousands of jobs and also bring water reliability to an area of the country that has suffered through a devastating drought over the past few years.

Cadiz also overcame a number of environmental lawsuits under state law. As part of its decision the San Bernardino County supervisors established an independent enforcement role over the project’s operations and authorized groundwater withdrawals that will avoid harm to desert resources.

Environmentalists and desert advocates, however, have decried the project, arguing that the project could deplete water needed to support the local wildlife and cause dust storms that would affect regional air quality.

Federal hydrologists have challenged Cadiz’s assertions about the rate of natural recharge of the desert aquifer. Public land advocates say that any pumping will dry up the natural springs on surrounding federal land.

“Many of the springs and seeps are going to dry up because of groundwater extraction,” Ileene Anderson, a biologist with the Center for Biological Diversity, told The Press Enterprise.

Sen. Diane Feinstein, who authored the California Desert Protection Act and was instrumental in creating the nearby Mojave Trails National Preserve, has been one of the biggest opponents of Cadiz. The California Democrat has for years attached riders to congressional appropriations bills preventing the BLM from spending money that would benefit the Cadiz project.

“The Trump administration wants to open the door for a private company to exploit a natural desert aquifer and destroy pristine public land purely for profit,” Feinstein said in a statement. “The administration is completely undermining federal oversight of railroad rights-of-way.”

Despite the pushback from Feinstein, the project enjoys a good deal of support in Congress. Rep. Rob Bishop of Utah – the chairman of the House Natural Resources Committee – was one of 18 members of Congress to urge Interior Secretary Ryan Zinke to revoke the BLM directives.